The weight of the mass found at Otumpa, in the Gran Chaco Gualamba, in South America, by Don Rubin de Celis (1783) was estimated at about fifteen tons. A piece from this mass, weighing 1,400 pounds, is now in the British Museum. As we see from the example of the Esquimaux, whom Captain Ross (1819) found in possession of knives and harpoons which they had made from masses of meteoric iron, the discovery was probably made at a very remote period, while man was still in the savage state; but iron having once become known, the desire to obtain it in larger quantities from other sources naturally grew with the progress of civilisation, and gradually led to the knowledge of its ores and of the art of utilising them. Thus there can hardly be a doubt that iron-smelting was practised long before historic times. In India and China the origin of its use loses itself in the remotest antiquity; and the imposing monuments of ancient Egypt, many of which are at least five thousand years old, could not possibly have been erected without the aid of iron. In the Book of Deuteronomy (iv. 20) the land of Egypt is compared to an iron-furnace—a figurative expression which shows that even at that early period iron- smelting must have been a well-known branch of industry. The iron weapons found in the lacustrine dwellings of Switzerland likewise point to a very ancient use of iron in Central Europe, no less than the fact mentioned by Cæsar, that during the siege of Avaricum (Bourges) the works erected by the Romans for taking the town were repeatedly destroyed by the subterranean galleries of the besieged, who, as the conqueror relates, were accustomed to such underground labour from their habitually working in iron-mines, an industry which, to judge from this passage, must even then have been of ancient date in Gaul. For many ages the uses of iron remained chiefly confined to the instruments of agriculture and of war—to the ploughshare and the sword. With the progress of civilisation its employment extended to many purposes unknown before; and in our times the construction of ships and buildings, of railroads and bridges, absorbs quantities which would have appeared incredible almost within the memory of living man. Hence the manufacture of iron has made more rapid progress since the beginning of the present century than in any former period of the world’s history, and even the present immense production scarcely keeps pace with a demand to which it is not easy to assign a limit.